Calibration data tables in automotive applications typically represent a collection of discrete values that approximate a desired analog function. In order to more closely approximate the analog function in practice, known data interpolation techniques are typically used to determine calibration data that falls between the discrete table entries, and in a two-dimensional table, such interpolation requires knowledge of foul adjacent table entries. For example, if data entries in a particular calibration data table are designated as “D”, then data items Di,j, Di,j+1, Di+1 1,j and Di+1,j+1 will be required to interpolate data values between rows i and i+1 and columns j and j+1.
Data tables in general can be quite large and therefore require a significant amount of memory capacity for storage thereof. It is accordingly desirable to compress such data tables into smaller blocks of data that consume less memory. It is also desirable with compressed calibration data tables to preserve the ability to quickly and efficiently retrieve adjacent table entries for data interpolation as just described. The present invention is directed to data table compression techniques designed to achieve each of these goals, both separately and in combination.